Land Rover Range Rover Etm 1995 4th Edition Rover Manual

							CRUISE CONTROLB5
16TROUBLESHOOTING
On
Test C
OKOK
OKOK
1C
2C
2C
GO TO TEST D
PROBLEM CAUSE
YS,R Wire -
-
Rotary Coupler
Steering Wheel Switches -PROBLEM CAUSE
Cruise Control Converter/In-
verter Module -
Less than 1 ohm
Z249
Cruise Control Con-
verter/Inverter Module CONDITIONS
Ignition Switch
Position: 0
RESULTS

Steering Wheel Switches
SET/ACCEL Switch


Off More than 10K ohms

 
C241P
YS
= = CONDITIONS
Ignition Switch
Position: II
BAT VOLT


C243 SY
Cruise Control Switch
On


RESULTS
Steering Wheel Switches
SET/ACCEL Switch


On
Off=
=
0 V
V
Z121
Cruise Control ECU 
						

							CRUISE CONTROLB5
17TROUBLESHOOTING
Test D
OKOKPROBLEM CAUSE
OKOK
3D 1D
2D
GP Wire -
-
2D
W Wire
Stop Lamp Switch -
PROBLEM CAUSE
OR, ON Wire -
-
Brake Switch Vent Valve
Body Electrical Control
Module (BECM) -
Released
Z121
Cruise Control ECU CONDITIONS
Ignition Switch
Position: II
RESULTS

Brake Pedal
Depressed


BAT VOLT
0 V


C243
GP
=
=
CONDITIONS
Ignition Switch
Position: II
BAT VOLT


C243 OR
Cruise Control Switch
On


RESULTS
Brake Pedal


Depressed
Released=
=0 V
V
Z121
Cruise Control ECU Transfer Box
Hi Range


Gear Selector
Forward Gear

 
						

							CRUISE CONTROLB5
18TROUBLESHOOTING
OKOKPROBLEM CAUSE
OKOK
3D
4D
CONDITIONS
Ignition Switch
Position: II
Y,  Y R
CONDITIONS
Ignition Switch
Position: II
Wire -
-



4D


Cruise Control Switch
On
Body Electrical Control
Module (BECM)
2D
PROBLEM CAUSE
OU, OR -
-
Cruise Control Vacuum
Pump Turn a drive wheel by hand


RESULTS
=
C243 YR
V
Z121
Cruise Control ECU Y LHD
RHD5V with ignition position II
RESULTS
Cruise Control Vacuum Pump
Operates


C243
Z121
Cruise Control ECU
OR
OU
OR
Wire
5D
Transfer Gearbox
Hi Range


Gear Selector
Forward Gear


Brake Pedal
Released

=
2.5V approx. with wheels turning 
						

							CRUISE CONTROLB5
19TROUBLESHOOTING
BAT VOLT
OKOKPROBLEM CAUSE
OKOK
5D
1E
CONDITIONS
Ignition Switch
Position: II
OK
CONDITIONS
Ignition Switch
Position: II
Wire -
-

 



Cruise Control Switch
On
Cruise Control Vacuum
Pump
Test E
4D
PROBLEM CAUSE
Cruise Control ECU -
GO TO TEST F
C243
Z121
Cruise Control ECU
Gear Selector
Forward Gear




Clutch Pedal
Released
Cruise Control Switch
On


RESULTS
Cruise Control Vacuum Pump
Operates


Throttle Opens Wide Valve Closes
OK
OR
Z249
Cruise Control Con-
verter/Inverter Module

 VC241DOW
B
RESULTS
2E
Transfer Gearbox
Hi Range


Gear Selector
Forward Gear


Brake Pedal
Released


OU
OR 
						

							CRUISE CONTROLB5
20TROUBLESHOOTING
OKOKPROBLEM CAUSE
OKOK
2E
3E
CONDITIONS
Ignition Switch
Position: 0
B
CONDITIONS
Ignition Switch
Position: 0
Wire -

 

3E


Cruise Control Switch
On
1E
PROBLEM CAUSE
WY Wire -
-
B Wire
Cruise Control Switch -PROBLEM CAUSE
OW Wire -
-
Body Electrical Control
Module (BECM) RESULTS
Less than 1 ohm


RESULTS
Less than 1 ohm 
Z249
Cruise Control Con-
verter/Inverter Module

 

C241D
B
Z238
Body Electrical
Control Module
(BECM)

 

C255
WY 
						

							CRUISE CONTROLB5
21TROUBLESHOOTING
Test F
OKOKPROBLEM CAUSE
OKOK
3F 1F
2F
CONDITIONS
Ignition Switch
Position: II
BAT VOLT
GB Wire -
- 

2F
Stop Lamp Switch
PROBLEM CAUSE
YP Wire -
-
Stop Lamp Switch RESULTS
Brake Pedal


Depressed
Released
= =0 V
CONDITIONS
Ignition Switch
Position: II
BAT VOLT


RESULTS
Brake Pedal


Depressed
Released
= =
0 V
       	 
 
        	 


        	 
 
       
	 
 
        	 
 
     
Z132
Engine Control Mod-
ule (ECM)
 V
GP
       	 
 
        	 


        	 
 
       
	 
 
        	 
 
     
Z132
Engine Control Mod-
ule (ECM)

 V
YP
C572
C572 
						

							CRUISE CONTROLB5
22TROUBLESHOOTING
OKOKPROBLEM CAUSE
OKOK
5F 3F
4F
CONDITIONS
Ignition Switch
Position: II
Y,  Y G
CONDITIONS
Ignition Switch
Position: 0
RESULTSWire -
-

 

4F
Body Electrical Control
Module (BECM)
2F
PROBLEM CAUSE
OY, YO Wire - Turn a drive wheel by hand


RESULTS
       	 
 
        	 


        	 
 
       
	 
 
        	 
 
     
Z132
Engine Control Mod-
ule (ECM)

 V
Y
C572
Less than 1 ohm
       	 
 
        	 


        	 
 
       
	 
 
        	 
 
     
Z132
Engine Control
Module (ECM)
YO
C572
C241D
Z249
Cruise Control Converter/
Inverter Module
OY
=4V Fluctuating

 
						

							CRUISE CONTROLB5
23TROUBLESHOOTING
OKOKPROBLEM CAUSE
OKOK
5F
6F
CONDITIONS
Ignition Switch
Position: 0
YR, W Wire -
- 

6F
B, PB Wire
Rotary Coupler -
4F
PROBLEM CAUSE
YS, R Wire -
-
Rotary Coupler
Steering Wheel Switches -PROBLEM CAUSE
Cruise Control Converter/
Inverter Module - RESULTS
Steering Wheel Switches


On
OffLess than 1 ohm
More than 10K ohms=
=
RES/DECEL SwitchZ249
Cruise Control Con-
verter/Inverter Mod-
ule


C241D
YR
Steering Wheel Switches -
CONDITIONS
Ignition Switch
Position: 0


RESULTS
Steering Wheel Switches


On
OffLess than 1 ohm
More than 10K ohms=
=
SET/ACCEL SwitchZ249
Cruise Control Con-
verter/Inverter Mod-
ule

C241D
YS
Body Electrical Control
Module (BECM) - 
						

							TRANSFER GEARBOXB6
CIRCUIT OPERATION1
CIRCUIT OPERATION
Interface to transfer motor inside Transfer Box
(X313)
The Transmission Gearbox Control Unit (Z256) has
a seven wire interface to the Transfer Motor inside
the Transfer Box (X313), consisting of the four motor
position switches, the ground for the switches and
the drives to move the motor one way or the other.
Motor Position Switches±
pins 17, 32, 33, 7
The Transmission Gearbox Control Unit (Z256)
reads the position of the motor in the form of a
binary Gray Code.
So the Transmission Gearbox Control Unit (Z256)
can find out in which gear the Transfer Box (X313) is
in and where the motor should move to, to engage
the desired range. If the Transfer Box (X313) moves
outside the normal modes (e.g. Left of High) then the
Transmission Gearbox Control Unit (Z256) can move
the motor back to the correct position.
Motor Position Switch ground±
pin 19
The switches on the transfer box motor are
referenced to pin 19, i.e. if there is a problem with
the harness to pin 19 then the Transmission
Gearbox Control Unit (Z256) will not be able to
assess where the transfer motor is and so will not
move the motor.
Motor drive Clockwise (pins 25, 26) and Counter
Clockwise (pins 1, 2)
The Transmission Gearbox Control Unit (Z256)
receives signals from the motor position switches,
the drivers request, the vehicle speed and the
transmission neutral signal and, when the
parameters are correct, powers the motor from one
mode to another via the motor drives. This is actually
a single wire interface for each direction which is
split down to two wires at the Transmission Gearbox
Control Unit (Z256) to help pass the current though
two pins rather than one. If there is a problem with
either the motor drives or the harness, then the
motor will not move and a range change will not be
possible.
Vehicle Speed Sensor±
pins 13, 30
The Transmission Gearbox Control Unit (Z256)
senses how fast the vehicle is travelling, compares
this speed to the value stored in the memory and
decides if a range change is allowed. Presently the
shift speeds are set at 5 mph High to Low and Low
to High on vehicles with an automatic transmissionand 15 mph Low to High on vehicles with a manual
transmission.
Interface to BeCM (Z238)
High, Low and Neutral Status Lamps
±
pins 35, 14, 36
The Transmission Gearbox Control Unit (Z256)
informs the BeCM (Z238), which informs the
Instrument Pack (Z142), about the range the vehicle
is in via three status lamps.
When a range change is requested, the desired
range will flash up on the display (i.e. ªHIGHº) and
continue flashing until the range change is achieved.
When complete, the range message will switch to
constant and be displayed for a few seconds.
If a range change is requested and not all of the
conditions are satisfied then the desired range
message will flash and continue flashing until all of
the parameters are satisfied or the request is
removed.
If the transfer box neutral is selected then, after a
five second safety delay, the Transfer Box (X313)
moves to neutral and the display shows ªNEUTRALº.
The High and Low status lamp signals also pass
information to the H±Gate and the Auto Gear Box
Control Unit (Z255).
Interface to Engine Control Module 
(ECM) (Z132)
On North American Specification (NAS) vehicles, the
inability of the Transfer Gear Box ECU (Z256) to
move into the High range is flagged over the fault
output line. A fault will also be flagged in the event of
a speed sensor failure or incorrect transfer motor
position information. The Malfunction Indicator Lamp
(MIL) will illuminate if a fault is recorded on two
successive journeys. 
						

							TRANSFER GEARBOXB6
CIRCUIT OPERATION2
Neutral Switch (X308) or Clutch Switch±
pin 34
A shift between ranges is possible when the
transmission is in neutral. The Transmission
Gearbox Control Unit (Z256) senses this via a
Park/Neutral Switch (X308) on automatic
transmission vehicles and via either a clutch switch
or a lever neutral switch on manual transmission
vehicles. This signal is passed via the BeCM (Z238).
Interface to ªH± Gateº±
pin 35, 15 (automatic
transmission only)
The H±Gate gets the range information via a High
and Low status signal from the output of the
Transmission Gearbox Control Unit (Z256);
e.g. when the vehicle is in High then the High side of
the ªHº is illuminated. When a range change to Low
is requested, the Low side of the ªHº starts to flash
whilst the High side stays constant. When Low range
is obtained then the flashing light on the Low side
changes to constant and the High side light goes off.
If a range change is requested and not all of the
conditions are satisfied, then the current range will
stay illuminated and the desired range will flash and
continue flashing until all of the parameters are
satisfied or the request is removed.
If the gear lever is placed in the neutral position for
the gearbox and the transfer box then, after a five
second safety delay, the transfer box moves to
neutral and the lights on both side of the ªHº are
extinguished.
Interface to Auto Gear Box Control Unit (Z255)
± pin 35
The High/Low signal to the Auto Gear Box Control
Unit (Z255) comes from the High range status lamp.
If the Auto Gear Box Control Unit (Z255) does not
receive the range information, then an incorrect gear
change mode could be selected, i.e. Manual rather
than Sport in High range and vice versa in Low
range. Also, the shift strategy is different between
the Economy modes of High and Low and so poor
shift quality could result.
Automatic Selector Park Interlock
When the gear selector lever is in the  park position,
the shift interlock solenoid is deenergized and
prevents the selector from being moved to another
gear. To free the selector, the Ignition Switch (X134)
must be in position II and the brake pedal must be
depressed.Current is then supplied to the solenoid through the
PR wire via fuse 13. The solenoid is grounded using
the B wire to the console ground E621.
The solenoid is now energised, freeing the selector.
The solenoid is energised continuously whilst the
selector lever is in any position other than park and
the Ignition Switch (X134) is in position II.